Detachable cylinder head constructions for liquid cooled fuel injection compression ignition engines



2,785,664 DETACHABLE CYLINDER HEAD CONSTRUCTIONS FOR C. N. GOLDSMITHFiled May 23, 1955 March 19, 1957 LIQUID COOLED FUEL INJECTIONCOMPRESSION IGNITION ENGINES IINVENTQR CHARLES N. GoLDsmrrH vg 61, Mm YATTORNEYS DETACHABLE CYLINDER HEAD CONSTRUC- TIONS FOR LIQUID COOLEDFUEL INJEC- TION COIVIPRESSION IGNITION ENGINES Charles NormanGoldsmith, Shoreham-by-Sea, England, assignor to Ricardo & Co.,Engineers (i327) Limited, London, England, a company of Great BritainThis invention relates to cylinder head constructions for liquid cooledcompression ignition engines of the liquid fuel injection type.

It is an object of the invention to provide improved cooling of a fuelinjector arranged in the cylinder head.

According to the present invention a liquid cooled cylinder head for anengine of the kind referred to includes an injector housing extendingacross the liquid cooling space of the cylinder head, from the outerwall of such space to the inner wall lying adjacent the cylinder bore,and formed integral with or making fluid-tight engagement with each ofsuch walls, and an internal diaphragm wall surrounding but spaced by anannular clearance from the injector housing, and extending across theliquid cooling space so as to divide it into two chambers communicatingwith one another through the clearance space between the housing and thediaphragm wall, inlet and outlet passages for flow of cooling liquidthrough the cylinder head being so arranged that a flow of coolingliquid is caused to take place between such chambers 1 through suchclearance space.

It will be seen that by suitable choice of dimensions the velocity ofthe cooling liquid stream passing round the injector housing may beincreased, with resultant increase in the cooling etfect. Moreover thearrangement is preferably such that the flow of cooling liquid takesplace from the chamber in which the outer end of the housing lies, intothe chamber in which the inner end of the housing lies, so that coolingliquid tends to impinge upon the inner face of the inner wall of thehead, immediately around the inner end of the housing.

In a preferred construction the axis of the injector housing is inclinedto the axis of the respective engine United States Patent O cylinder,and the diaphragm wall includes an annular portion surrounding theinjector housing and arranged sub-.

stantially in a plane normal to the axis of the injector housing.

In any case the diaphragm wall is preferably provided with a smallaperture adjacent its upper end to permit the escape of air or steamwhich may accumulate on one side of this wall.

The invention may be performed in various different ways but onespecific embodiment will now be described by way of example withreference to the accompanying drawings, in which,

Figure 1 is a fragmentary sectional side elevation through a cylinderhead, including part of the associated cylinder block, and,

Figure 2 is a fragmentary sectional plan view on the line II-Il inFigure 1.

In this example the compression ignition engine comprises a waterjacketed cylinder block 10 with a detachable water cooled cylinder head11. The cylinder head is formed with a lower inner wall 12 having a flatsurface to engage the upper surface 13 of the cylinder block with theusual interposed gasket seal 14, and an upper outer wall 15 which formsa cooling water cavity with the inper wall 12, with the usual inlet 16and exhaust 17 passages extending between the inner and outer walls andcommunicating with inlet and exhaust ports in the inner wall 12controlled by poppet valves 18, 19.

A bore 20 to receive a fuel injection nozzle is provided in the innerwall 12 of the cylinder head, over each cylinder bore, and the head ofeach piston closely approaches the inner wall of the cylinder head atthe top of its strokeand is formed with a combustion cavity 21 oppositethe bore for the fuel nozzle. The cylinder head construction includes acylindrical injector housing 22 extending through the water cavity inthe head with its lower end located in watertight manner in a recess 23in the inner wall 12 of the head, and its outer end similarly secured inwatertight manner to the outer wall 15 of the head.

The injector 22 is inclined to the cylinder axis and-the recess 23 iscorrespondingly inclined in a raised portion formed on the upper surfaceof the inner wall of the cylinder head. Each injector housing may forexample be inclined to the axis of the respective cylinder at an angleof approximately 20. The fuel injector itself 24 is mounted within theinjector housing 22 and the nozzle 25 extends through an aperture in thelower end of the housing 22 and through the bore 20 in the inner wall ofthe head.

The cylinder head in the neighbourhood of the injector housing 22 isformed with an internal apertured diaphragm wall or web 30 lying betweenits inner wall 12 and outer walls 15 and including an annular portion 31lying in a plane normal to the axis of the injector housing 22 andsurrounding but spaced therefrom. The diaphragm wall thus provides anannular aperture 32 surrounding the injector housing. Cooling water isadmitted tothe water jacket of the cylinder block through an inlet 33,and passes upwards through an aperture 34 in the upper wall of thecylinder block and a corresponding aperture 35 in the inner wall of thecylinder head into the chamber on the upper side of the diaphragm wall30, and thence downwards through the annular aperture 32 surrounding theinjector housing into a chamber surrounding the lower end of thehousing. Due to the restricted cross section of the annular aperture 32the velocity of the cooling water stream through the aperture isincreased, with consequent increased cooling efliciency. Moreover therelatively high velocity stream of water issuing into the lower chamberis directed along the sides of the lower end of the injector housing 22and impinges on the upper surface of the inner wall 12 of the cylinderhead immediately surrounding the injector housing, and thus providesefiicient cooling of the lower end of the injector and the adjacentparts of the inner wall of the cylinder head.

From the lower chamber the cooling water passes through the main watercavity in the cylinder head to the usual exit 36. It will be understoodalso that instead of supplying cooling water to the cylinder headthrough apertures in the mating surfaces of the cylinder head and thecylinder block, the cooling water may be supplied to the head by anexternal connection.

To allow air and steam to escape from the chamber on the upper side ofthe diaphragm wall 30, a small aperture 37 is provided in this chamberadjacent the outer wall of the cylinder head through which air and steammay escape from such chamber into the main cavity of the cylinder headand thence to relief.

What I claim as my invention and desire to secure by Letters Patent is:V

l. A liquid cooled cylinder head assembly for a liquid fuel injectioncompression ignition engine including an injector housing extendingacross the liquid cooling space of. the cylinder head from the outerwall of such space to the inner wall lying adjacent the cylinder boreand mak enema Mar. 19, 1957 a ance space between the housing1aridfthesaid-diaphragm wall the two ends: of the injectorhousing lyingrespectively inlathe;said;two chambers, inlet and outlet passages for.

, flow of cooling,liquid:through:the:cylinder-headheing so arranged,that.:a ,flow of cooling :liquid :is caused to take place between ;suchchambers through :suchiclearance space and to impinge on the :inner faceof the inner wall 7 0f 'the:head.imm ediately,a1:ound.:theendwfthexhousin'g.

-2.,A liquid-cooled icylinder. head LmnStmctiQn claimed in claim lsinwhich the axis of ma-injector ihousing inclined ito the axisz-of therespective engine cylinder, :and the diaphragm iwall includesflanannular-portion surrounding xtheainjectorr housing and an-rangedsubstantially in a plane normal to the axis of the injector houa'claimed 'inclaim 1 'in which the diaphragm wall is p rovidcd with,aismall aperture adjacent its upper .endetoper: mit the escape of air orvapour which may accumulate on one side of this wall. V

4. A liquid-cooled cylinder head construction as i claimed in claim 1 inwhichtheinjector housing is separate from theinjector assembly iteelfand'is arranged as a semirpemianent and liquid-tightffitt tlg in thecylinder head. t 1 1 J 'Ref ereuces Clteglin the {file ofthis patent IUNITED STATES PATENTS,

1,107,946 Hesselman ..;Aug. 18, 1914 1,857,744 Schaef May TO, 19322,096,344 tSchlaupitz 0ct. -1 9, 3937 2,730,085 Brill t-. Jan. 10, 1956

